1. Field of the Invention
This invention relates generally to the field of two way messaging systems. More particularly, this invention relates to a non-real time two way messaging system which utilizes data compression to minimize transmission time and thus conserve battery life and optimize bandwidth utilization.
2. Background of the Invention
Two way radio systems have been in use for a number of years to facilitate two way communication between parties. However, use of these systems has largely been limited to specialized business applications (e.g. security), police, government and military use due to the cost and bulk of the devices. Consumers have found pagers and cellular telephone devices to provide a more convenient mechanism for everyday communication needs both for business and private use. Unfortunately, the cost of use of cellular telephones remains high for some users and paging devices generally permit only one way communication, thus requiring access to a telephone to enable the user to provide a response.
Recently, personal two way messaging systems (such as Motorola's Tango and Tenor pagers) which provide limited two way messaging capability have become available. Like pagers, such two way messaging systems are designed to be personal devices which are compact and easy to carry. Unfortunately, the convenience of small size and weight limits the size of the battery used to power such devices. As a result, substantial efforts have been devoted to the problem of optimizing battery drain in such devices in order to maximize the battery life for these devices. Moreover, the availability of bandwidth is problematic and thus use of the available bandwidth should be optimized.